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1. First Indication of Solar ${}^8\mathrm{B}$ Neutrinos via Coherent Elastic Neutrino-Nucleus Scattering with XENONnT

   https://doi.org/10.1103/PhysRevLett.133.191002  

   Aprile, E; Aalbers, J; Abe, K; Ahmed_Maouloud, S; Althueser, L; Andrieu, B; Angelino, E; Antón_Martin, D; Arneodo, F; Baudis, L; et al (November 2024, Physical Review Letters)

   We present the first measurement of nuclear recoils from solar ${}^8\mathrm{B}$ neutrinos via coherent elastic neutrino-nucleus scattering with the XENONnT dark matter experiment. The central detector of XENONnT is a low-background, two-phase time projection chamber with a 5.9 t sensitive liquid xenon target. A blind analysis with an exposure of $3.51\mathrm{t}\times \mathrm{yr}$ resulted in 37 observed events above 0.5 keV, with ( ${26.4}_{-1.3}^{+1.4}$ ) events expected from backgrounds. The background-only hypothesis is rejected with a statistical significance of $2.73\sigma$ . The measured ${}^8\mathrm{B}$ solar neutrino flux of $\left({4.7}_{-2.3}^{+3.6}\right)\times {10}^6{\mathrm{cm}}^{-2}{\mathrm{s}}^{-1}$ is consistent with results from the Sudbury Neutrino Observatory. The measured neutrino flux-weighted $\mathrm{CE}\nu \mathrm{NS}$ cross section on Xe of $\left({1.1}_{-0.5}^{+0.8}\right)\times {10}^{-39}{\mathrm{cm}}^2$ is consistent with the Standard Model prediction. This is the first direct measurement of nuclear recoils from solar neutrinos with a dark matter detector. Published by the American Physical Society2024 

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2. Measurement of the Isolated Nuclear Two-Photon Decay in ${}^{72}\mathrm{Ge}$

   https://doi.org/10.1103/PhysRevLett.133.022502  

   Freire-Fernández, D; Korten, W; Chen, R J; Litvinov, S; Litvinov, Yu A; Sanjari, M S; Weick, H; Akinci, F C; Albers, H M; Armstrong, M; et al (July 2024, Physical Review Letters)

   The nuclear two-photon or double-gamma ( $2\gamma$ ) decay is a second-order electromagnetic process whereby a nucleus in an excited state emits two gamma rays simultaneously. To be able to directly measure the $2\gamma$ decay rate in the low-energy regime below the electron-positron pair-creation threshold, we combined the isochronous mode of a storage ring with Schottky resonant cavities. The newly developed technique can be applied to isomers with excitation energies down to $\sim 100\mathrm{keV}$ and half-lives as short as $\sim 10\mathrm{ms}$ . The half-life for the $2\gamma$ decay of the first-excited $0^{+}$ state in bare ${}^{72}\mathrm{Ge}$ ions was determined to be 23.9(6) ms, which strongly deviates from expectations. Published by the American Physical Society2024 

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3. Measurement of $CP$ asymmetries in $B^0\to K_S^0{K}_S^0{K}_S^0$ decays at Belle II

   https://doi.org/10.1103/PhysRevD.109.112020  

   Adachi, I; Aggarwal, L; Ahmed, H; Aihara, H; Akopov, N; Aloisio, A; Anh_Ky, N; Asner, D M; Atmacan, H; Aushev, T; et al (June 2024, Physical Review D)

   We report a measurement of decay-time-dependent charge-parity ( $CP$ ) asymmetries in $B^0\to K_S^0{K}_S^0{K}_S^0$ decays. We use $387\times {10}^6$ $B\overline{B}$ pairs collected at the $\mathrm{\Upsilon }\left(4S\right)$ resonance with the Belle II detector at the SuperKEKB asymmetric-energy electron-positron collider. We reconstruct 220 signal events and extract the $CP$ -violating parameters $S$ and $C$ from a fit to the distribution of the decay-time difference between the two $B$ mesons. The resulting confidence region is consistent with previous measurements in $B^0\to K_S^0{K}_S^0{K}_S^0$ and $B^0\to \left(c\overline{c}\right)K^0$ decays and with predictions based on the standard model. Published by the American Physical Society2024 

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4. Search for two-body $B$ meson decays to ${\mathrm{\Lambda }}^0$ and ${\mathrm{\Omega }}_c^{(*)0}$

   https://doi.org/10.1103/PhysRevD.110.L031102  

   Savinov, V; Adachi, I; Ahn, J K; Aihara, H; Asner, D M; Atmacan, H; Ayad, R; Banerjee, Sw; Bennett, J; Bessner, M; et al (August 2024, Physical Review D)

   We report the results of the first search for Standard Model and baryon-number-violating two-body decays of the neutral $B$ mesons to ${\mathrm{\Lambda }}^0$ and ${\mathrm{\Omega }}_c^{(*)0}$ using $711{\mathrm{fb}}^{-1}$ of data collected at the $\mathrm{\Upsilon }\left(4S\right)$ resonance with the Belle detector at the KEKB asymmetric-energy $e^{+}{e}^{-}$ collider. We observe no evidence of signal from any such decays and set 95% confidence-level upper limits on the products of $B^0$ and ${\overline{B}}^0$ branching fractions for these two-body decays with $\mathcal{B}({\mathrm{\Omega }}_c^0\to {\pi }^{+}{\mathrm{\Omega }}^{-})$ in the range between $9.5\times {10}^{-8}$ and $31.2\times {10}^{-8}$ . Published by the American Physical Society2024 

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5. Study of ${\mathrm{\Lambda }}_b^0$ and ${\mathrm{\Xi }}_b^0$ Decays to $\mathrm{\Lambda }{h}^{+}{h}^{\prime -}$ and Evidence for $CP$ Violation in ${\mathrm{\Lambda }}_b^0\to \mathrm{\Lambda }{K}^{+}{K}^{-}$ Decays

   https://doi.org/10.1103/PhysRevLett.134.101802  

   Aaij, R; Abdelmotteleb, A_S W; Abellan_Beteta, C; Abudinén, F; Ackernley, T; Adefisoye, A A; Adeva, B; Adinolfi, M; Adlarson, P; Agapopoulou, C; et al (March 2025, Physical Review Letters)

   A study of ${\mathrm{\Lambda }}_b^0$ and ${\mathrm{\Xi }}_b^0$ decays to $\mathrm{\Lambda }{h}^{+}{h}^{\prime -}$ ( $h^{(\prime )}=\pi ,K$ ) is performed using $pp$ collision data collected by the LHCb experiment during LHC Runs 1–2, corresponding to an integrated luminosity of $9{\mathrm{fb}}^{-1}$ . The branching fractions for these decays are measured using the ${\mathrm{\Lambda }}_b^0\to {\mathrm{\Lambda }}_c^{+}(\to \mathrm{\Lambda }{\pi }^{+}){\pi }^{-}$ decay as a control channel. The decays ${\mathrm{\Lambda }}_b^0\to \mathrm{\Lambda }{\pi }^{+}{\pi }^{-}$ and ${\mathrm{\Xi }}_b^0\to \mathrm{\Lambda }{K}^{-}{\pi }^{+}$ are observed for the first time. For decay modes with sufficient signal yields, $CP$ asymmetries are measured in the full and localized regions of the final-state phase space. Evidence is found for $CP$ violation in the ${\mathrm{\Lambda }}_b^0\to \mathrm{\Lambda }{K}^{+}{K}^{-}$ decay, interpreted as originating primarily from an asymmetric ${\mathrm{\Lambda }}_b^0\to N^{*+}{K}^{-}$ decay amplitude. The measured $CP$ asymmetries for other decays are compatible with zero. © 2025 CERN, for the LHCb Collaboration2025CERN 

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